/*
 * TeleStax, Open Source Cloud Communications  Copyright 2012.
 * and individual contributors
 * by the @authors tag. See the copyright.txt in the distribution for a
 * full listing of individual contributors.
 *
 * This is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation; either version 2.1 of
 * the License, or (at your option) any later version.
 *
 * This software is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this software; if not, write to the Free
 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
 */

package org.mobicents.protocols.ss7.cap.primitives;

import java.io.IOException;
import java.util.Arrays;
import org.mobicents.protocols.asn.AsnException;
import org.mobicents.protocols.asn.AsnInputStream;
import org.mobicents.protocols.asn.AsnOutputStream;
import org.mobicents.protocols.asn.Tag;
import org.mobicents.protocols.ss7.cap.api.CAPException;
import org.mobicents.protocols.ss7.cap.api.CAPParsingComponentException;
import org.mobicents.protocols.ss7.cap.api.CAPParsingComponentExceptionReason;


/**
*
* Super class for implementing primitives that are OCTET STRING (SIZE (x..y))
* 
* @author sergey vetyutnev
* 
*/
public class OctetStringBase implements CAPAsnPrimitive {

	protected byte[] data;

	protected int minLength;
	protected int maxLength;
	protected String _PrimitiveName;

	public OctetStringBase(int minLength, int maxLength, String _PrimitiveName) {
		this.minLength = minLength;
		this.maxLength = maxLength;
		this._PrimitiveName = _PrimitiveName;
	}

	public OctetStringBase(int minLength, int maxLength, String _PrimitiveName, byte[] data) {
		this(minLength, maxLength, _PrimitiveName);

		this.data = data;
	}


	public int getTag() throws CAPException {
		return Tag.STRING_OCTET;
	}

	public int getTagClass() {
		return Tag.CLASS_UNIVERSAL;
	}

	public boolean getIsPrimitive() {
		return true;
	}

	@Override
	public void decodeAll(AsnInputStream ansIS) throws CAPParsingComponentException {

		try {
			int length = ansIS.readLength();
			this._decode(ansIS, length);
		} catch (IOException e) {
			throw new CAPParsingComponentException("IOException when decoding " + _PrimitiveName + ": " + e.getMessage(), e,
					CAPParsingComponentExceptionReason.MistypedParameter);
		}
	}

	public void decodeData(AsnInputStream ansIS, int length) throws CAPParsingComponentException {

		try {
			this._decode(ansIS, length);
		} catch (IOException e) {
			throw new CAPParsingComponentException("IOException when decoding " + _PrimitiveName + ": " + e.getMessage(), e,
					CAPParsingComponentExceptionReason.MistypedParameter);
		}
	}

	protected void _decode(AsnInputStream ansIS, int length) throws CAPParsingComponentException, IOException {

		if (!ansIS.isTagPrimitive())
			throw new CAPParsingComponentException("Error decoding " + _PrimitiveName + ": field must be primitive",
					CAPParsingComponentExceptionReason.MistypedParameter);
		
		if (length < this.minLength || length > this.maxLength)
			throw new CAPParsingComponentException("Error decoding " + _PrimitiveName + ": the field must contain from " + this.minLength + " to "
					+ this.maxLength + " octets. Contains: " + length, CAPParsingComponentExceptionReason.MistypedParameter);

		data = new byte[length];
		ansIS.read(data);
	}
	
	public void encodeAll(AsnOutputStream asnOs) throws CAPException {
		
		this.encodeAll(asnOs, this.getTagClass(), this.getTag());
	}

	public void encodeAll(AsnOutputStream asnOs, int tagClass, int tag) throws CAPException {
		
		try {
			asnOs.writeTag(tagClass, this.getIsPrimitive(), tag);
			int pos = asnOs.StartContentDefiniteLength();
			this.encodeData(asnOs);
			asnOs.FinalizeContent(pos);
		} catch (AsnException e) {
			throw new CAPException("AsnException when encoding " + _PrimitiveName + ": " + e.getMessage(), e);
		}
	}

	public void encodeData(AsnOutputStream asnOs) throws CAPException {

		if (this.data == null)
			throw new CAPException("Error while encoding the " + _PrimitiveName + ": data is not defined");

		if (this.data.length < this.minLength || this.data.length > this.maxLength)
			throw new CAPException("Error while encoding the " + _PrimitiveName + ": data field length must be from " + this.minLength + " to "
					+ this.maxLength + " octets");

		asnOs.write(this.data);
	}

	@Override
	public int hashCode() {
		if (data == null)
			return 0;

		final int prime = 31;
		int result = 1;
		result = prime * result + Arrays.hashCode(data);
		return result;
	}

	@Override
	public boolean equals(Object obj) {
		if (this == obj)
			return true;
		if (obj == null)
			return false;
		if (getClass() != obj.getClass())
			return false;
		OctetStringBase other = (OctetStringBase) obj;
		if (data == null) {
			if (other.data != null)
				return false;
		} else if (!Arrays.equals(data, other.data))
			return false;
		return true;
	}

	@Override
	public String toString() {
		return _PrimitiveName + " [Data= " + this.printDataArr() + "]";
	}

	protected String printDataArr() {
		StringBuilder sb = new StringBuilder();
		boolean first = true;
		if (this.data != null) {
			for (int b : this.data) {
				if (first)
					first = false;
				else
					sb.append(", ");
				sb.append(b);
			}
		}

		return sb.toString();
	}
}

